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941.
942.
G.Dastgir Qureshi Philip S. Guzelian R.Marcus Vennart Herbert J. Evans 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1985,844(3):288-295
Because of the inherent difficulties of experimentation in intact animals, we used primary monolayer cultures of non-proliferating adult rat hepatocytes to study the effects of fibrinogen degradation products on fibrinogen biosynthesis. The freshly isolated hepatocytes obtained by collagenase perfusion of the liver in situ were cultured in a chemically defined serum-free medium. The rate of fibrinogen synthesis in control cultures was cells per 24 h. Additions of 20, 60 or 100 μg of homologous stage I fibrinogen degradation products had no effect on fibrinogen synthesis. In contrast, addition of the same amounts of homologous or heterologous (human) stage III fibrinogen degradation products resulted in a concentration-dependent increase in fibrinogen biosynthesis without affecting the rate of synthesis of albumin. When purified stage III fibrinogen degradation products D and E (human) were tested in 10, 30 or 50 μg/3 ml medium only fragment E showed a significant increase in fibrinogen biosynthesis (1.9-, 2.8- and 5.6-fold, respectively, over the control cultures). The presence of excess fibrinogen had no effect. These results suggest that fibrinogen fragment E may be a specific stimulator of fibrinogen biosynthesis which may play an important role in maintaining normal levels of plasma fibrinogen. 相似文献
943.
Herbert Schneckenburger Benno W. Reuter Siegfried M. Schoberth 《Trends in biotechnology》1985,3(10):257-261
The high specificity and sensitivity of fluorescence techniques have made them important analytical tools in medicine and biotechnology. Besides monitoring and quantitative detection of biomolecules these methods can be used for controlling bacterial activities or for measuring physiological states of cells or tissues. Three topics of importance in biotechnology — immunoassays, photosynthesis and fermentation — are treated in detail. 相似文献
944.
Peter Proksch Herbert Budzikiewicz Barry D. Tanowitzt Dale M. Smitht 《Phytochemistry》1984,23(3):679-680
The external leaf resins of four Hemizonia species afforded nine methylated flavonoids, including flavanones, flavones and flavonols. Besides the rare compounds 7-methyleriodictyol and 3,6,8-trimethoxy-5,7,3′,4′-tetrahydroxyflavone the new 6-methoxy-5,7,8,3′,4′-pentahydroxyflavone was isolated and identified by spectroscopic means. 相似文献
945.
E V Sivukhina G F Jirikowski H G Bernstein J G Lewis Z Herbert 《Hormones et métabolisme》2006,38(4):253-259
Corticosteroid-binding globulin, a specific steroid carrier in serum with high binding affinity for glucocorticoids, is expressed in various tissues. In the present study, we describe the immunocytochemical distribution of this protein in neurons and nerve fibers in the human hypothalamus. CBG immunoreactive perikarya and fibers were observed in the paraventricular, supraoptic, and sexual dimorphic nuclei in the perifornical region, as well as in the lateral hypothalamic and medial preoptic areas, the region of the diagonal band, suprachiasmatic and ventromedial nuclei, bed nucleus of the stria terminalis and some epithelial cells from the choroid plexus and ependymal cells. Stained fibers occurred in the median eminence and infundibulum. Double immunostaining revealed a partial co-localization of corticosteroid-binding globulin with oxytocin and, to a lesser extent, with vasopressin in the paraventricular and the supraoptic nuclei. Double immunofluorescence staining showed coexistence of these substances in axonal varicosities in the median eminence. We conclude that neurons of the human hypothalamus are capable of expressing corticosteroid-binding globulin, in part co-localized with the classical neurohypophyseal hormones. The distribution of CBG immunoreactive neurons, which is widespread but limited to specific nuclei, indicates that CBG has many physiological functions that may include neuroendocrine regulation and stress response. 相似文献
946.
Evaluation of the Duopath Legionella Lateral Flow Assay for Identification of Legionella pneumophila and Legionella Species Culture Isolates 下载免费PDF全文
Jürgen Herbert Helbig Paul Christian Lück Britta Kunz Andreas Bubert 《Applied microbiology》2006,72(6):4489-4491
Duopath Legionella (Merck KGaA, Darmstadt, Germany) is a new immunochromatographic assay for the simultaneous identification of cultured L. pneumophila and Legionella species other than L. pneumophila. In tests of 89 L. pneumophila strains and 87 Legionella strains other than L. pneumophila representing 41 different species, Duopath and a widely used latex agglutination assay detected L. pneumophila with 100% and 98% accuracy, respectively, whereas the percentages differed significantly for other Legionella spp. (93% versus 37% [P < 0.001]). Since many countries’ regulations require the identification of Legionella spp. in water and environmental samples, the use of Duopath Legionella to comply with those regulations could contribute to significantly fewer false-negative results. 相似文献
947.
Veronika ezáová Herbert Blum† Hana Hrelová Hannes Gamper‡ Milan Gryndler 《Global Change Biology》2005,11(2):224-230
Anthropogenic increases in atmospheric CO2 concentration and the connected deposition of organic matter into the soil influence the occurrence of decomposers who regulate carbon release back into the atmosphere. The effects of increased concentration of atmospheric carbon dioxide, plant species cover quality and nitrogen (N) fertilization on the coenosis composition of soil saprobic microfungi were studied under field conditions (Swiss Free Air Carbon Dioxide Enrichment experiment). In total, 42 species of microfungi were detected in examined soil. The most significant response of soil mycoflora was induced by the species identity of plant cover. Higher N fertilization significantly suppressed the abundance of soil microfungi at ambient CO2. The effect of increased CO2 on colony‐forming units was not significant when taken as an independent treatment; however, this factor interacted significantly with N availability. Some species, e.g. the Clonostachys rosea, were proven associated with the plant cover components, in this particular case with Trifolium repens. Therefore, we suggest the identity of plant species constituting plant cover as the most important factors affecting soil microfungi in agroecosystems. 相似文献
948.
H G Wiener P Klinkhamer U Schenck M Arbyn J Bulten C Bergeron A Herbert 《Cytopathology》2007,18(2):67-78
The quality of a cervical cytology laboratory depends on adequate handling and staining of the samples, screening and interpretation of the slides and reporting of the results. These guidelines give an overview of procedures recommended in Europe to manage the balance between best patient care possible, laboratory quality assurance and cost effectiveness and will be published as a chapter 4 in the European Guidelines for Quality Assurance in Cervical Cancer Screening. The laboratory guidelines include protocols for personnel and organisation, material requirements, handling and analysing cervical samples, recording of results, quality management and communication. The section on quality management is comprehensive and includes protocols for all aspects of internal and external quality assurance. The guidelines are extensively referenced and as far as possible the recommendations are evidence-based. 相似文献
949.
A. Herbert C. Bergeron H. Wiener U. Schenck P. Klinkhamer J. Bulten M. Arbyn 《Cytopathology》2007,18(4):213-219
There are many different systems of cytology classification used in the member states of the European Union (EU) and many different languages. The following short annexe to Chapter 3 of the European Guidelines for Quality Assurance in Cervical Cancer Screening provides a framework that will allow different terminologies and languages to be translated into standard terminology based on the Bethesda system (TBS) for cytology while retaining the cervical intraepithelial neoplasia (CIN) classification for histology. This approach has followed extensive consultation with representatives of many countries and professional groups as well as a discussion forum published in Cytopathology (2005;16:113). This article will describe the reporting of specimen adequacy, which is dealt with in more detail elsewhere in Chapter 3 of the guidelines, the optional general categorization recommended in TBS, the interpretation/cytology result and other comments that may be made on reports such as concurrent human papillomavirus testing and the use of automation review and recommendations for management. The main categories in TBS will be described in the context of CIN, dyskaryosis and dysplasia terminologies so that all may be translated into the same framework. These guidelines should allow European countries to adapt their terminology in such a way as to make their screening programmes comparable with each other as well as with programmes elsewhere in the world. 相似文献
950.
Katrin Bierhals Anna C Sondersorg Chiann-Tso Lin Claudia Rosenbaum Herbert Waldmann Frank Wehner 《Cellular physiology and biochemistry》2007,20(5):397-404
We were interested whether PKC alpha, delta, epsilon or zeta is the isoform actually employed in the activation of hypertonicity-induced cation channels (HICCs) in primary cultures of rat hepatocytes. Quantitative SDS-page and Western-blot experiments revealed that PKC alpha, delta and epsilon were stimulated by Indolactam V (as a DAG substitute for activation of c and nPKCs) but that only PKC delta and epsilon did respond to hypertonic stress. Furthermore, chelation of intracellular Ca(++) by BAPTA-AM did not alter HICC activation in cable-analysis experiments whereas Indolactam V as well as V8 (an Indolactam derivative specific for PKC delta and epsilon) activated HICC currents under isotonic conditions. Finally, by use of Rottlerin (as an inhibitor exhibiting a slight preference for PKC delta over epsilon) PKC epsilon could be identified as the most likely isoform responsible for the activation of the HICC. 相似文献